/**
 * UuidHelper
 */

  var UuidHelper = (function (){
      function getUuid(){
          // 长度
          var len = 32;
          // 进制
          var radix = 16;
          var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
          var uuid = [], i;
          radix = radix || chars.length;
          if (len){
              for (i=0; i<len; i++){
                  uuid[i] = chars[0 | Math.random() * radix];
              }
          } else {
              var r;
              uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
              uuid[14] = '4';
              for (i=0; i<36; i++){
                  if (!uuid[i]){
                    r = 0 | Math.random() * 16;
                    uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
                  }
              }
          }
          return uuid.join('');
      }

      return {
          generate: getUuid
      }
  })();

  module.exports = UuidHelper;
